JP2002525395A - Materials suitable for precision mesh-shaped polymerization processes and their use - Google Patents

Abstract

  (57) [Summary] The present disclosure describes a processing approach for rapid and efficient in situ polymerization of a specially prepared precursor mixture to achieve precise network shaping of products / articles with precise dimensions. This process is based on the use of a polymerizable composition consisting of a mixture of a dead polymer, a reactive plasticizer and an initiator, so that the composition is semi-solid-like and is partially polymerized before processing. As a result of its properties, it induces a low degree of shrinkage upon curing. This partially polymerized nature of the precursor mixture also allows highly impact resistant products / articles to be made. Other desired engineering properties can likewise be achieved by careful blending of the starting components in formulating the polymerizable (curable) mixture.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001] The present invention relates to the field of polymerization and molding. More specifically, the present invention relates to rapid in-situ, precision in-situ polymerization of semi-solid materials to provide dimensionally stable and accurate objects with little or no shrinkage upon curing.
itu near-net-shape polymerization. The invention further relates to useful semi-solid materials for use in this process.

BACKGROUND OF THE INVENTION Dimensionally accurate objects / articles find many applications in electronics, optics, automotive, aviation, and other high technology industries. Examples include: optically transmissive objects / articles, such as various precision lenses (spherical and aspheric), ophthalmic lenses (single vision, bifocal, trifocal, and progressive), contact lenses, Optical data storage disk substrate, and projection optics / lens array. There are a number of parts that are opaque but accurate in size (eg, couplers, housings, gears, and various packing assemblies). The simplest methods of producing precisely dimensioned parts are machining, grinding and polishing of sheet stock, and in fact this approach is still used today for some ophthalmic lenses. Unfortunately, this approach is costly because it is limited to simple shapes and requires a relatively large number of skilled workers to produce one part. More generally, the plastics industry relies on well-known processes such as injection molding, compression molding, transfer molding, reaction injection molding (RIM) and casting to produce parts with complex shapes.

[0003] Injection molding, compression molding and transfer molding require the use of thermoplastic polymers. The choice of material is limited to uncrosslinked polymers, which can be melted by heat and injected at high pressure. As an exemplary polymer,
Polymethyl methacrylate, polystyrene, ABS (acrylonitrile-butadiene-styrene) and polycarbonate. These molding processes require high temperatures and pressures; therefore, expensive molding equipment and molds are required. Large parts with thick cross-sections are difficult to mold due to the low rate of heat transfer. Long cycle times make the process uneconomical. In addition, finite coefficients of thermal expansion can result in component warpage during cooling. Therefore, these processes are hardly practical for mass production of components that require precise dimensions.

[0004] Reaction injection molding requires the use of at least two highly reactive components (A + B). Urethane is one such example, where the reactive components are monomeric isocyanates and alcohols. These components are mixed quickly and thoroughly just before injection into the mold cavity. The material can then be quickly set (cured) into the cavity. This technique relies on highly reactive and generally toxic materials. The mechanical means for thorough mixing is part of an integrated process, which adds cost to the production equipment. The manufactured parts are also less accurate in dimensions due to the shrinkage effects associated with the polymerization process. The choice of material is also limited by the required reaction chemistry. Therefore, reaction injection molding (RIM
) Are limited by highly reactive functional groups, mixing strength prior to mold filling, and the need for complex and expensive machinery to perform this process.

[0005] The manufacture of accurate parts has been attempted by a process commonly known as casting. Casting is typically an inexpensive alternative to the above process. This is also a more versatile process in which a large number of precursor mixtures (eg, monomers, crosslinkers, oligomers, etc.)
Can be formulated to achieve various end parts and performance characteristics. The final part can be thermoset and can be formed by a polymer network that is crosslinked to avoid melt flow. Since the precursor solution has a relatively low viscosity and promotes mold filling, the process is a low pressure operation, which reduces the required equipment costs. Unfortunately, this casting process is often compromised by the high shrinkage of the formulated precursor mixture, which produces incorrect parts in the wrapped shape. High shrinkage is a natural consequence of the use of precursors having low to moderate viscosities. By way of example, when referring to an ophthalmic lens, the mold defining the lens-shaped cavity generally consists of an anterior half and a posterior half, as well as an intervening gasket. The front mold half is concave, while the rear half is convex. Detailed design characteristics distinguish the usefulness of the resulting lens. Thus, if the in-situ curing process can be performed with precision mesh shape fidelity, and if so, simple vision lenses, bifocal lenses, trifocal lenses,
Progressive lenses, spherical lenses, aspheric lenses, and toroidal lenses can in principle all be produced. This is clearly a difficult task, at best if the material used for casting exhibits a high degree of shrinkage. Thus, casting is a mold filling step, an activation step to induce and maintain polymerization, and a mold opening / following to finish the part and re-use / re-shelf the mold halves. Requires a cleaning step. To date, all known casting processes begin with a polymerizable fluid that can be easily fed into the mold cavity (ie, moderate pressure). To minimize foam formation,
Caution must be taken. A carefully designed gasket is required, which is applied to seal the cavity formed by the mold halves. A controlled curing step is then imposed to convert the supplied liquid into a finished solid object.

[0006] Most curable formulations contain a carbon-carbon double bond. Such sites of unsaturation are exemplified by functional groups such as acrylates, methacrylates, vinyl ethers, and vinyl. The free radical or ionic polymerization mechanism can be triggered by a suitable initiator that is triggered either by UV or heat (ie,
Light or heat induced polymerization). Small molecule or organic mixtures are usually used to keep the viscosity low, as the reaction mixture must fill the cavity at one time in as short a time as possible to allow a suitable process economy . These systems have significant shrinkage upon curing, as high as 15% in some oligomer mixtures, and even higher than 20% in some small molecule formulations.

Further, the polymerization of unsaturated species is unfortunately an exothermic reaction. When such a reaction system is cured, a large amount of heat is generated. The result is a sharp rise in temperature of the cast part during curing, which often results in thermal decomposition, discoloration of the material, and warpage of the part during cooling and removal from the mold. This problem can be ameliorated by improving heat transfer. Unfortunately, heat transfer can be greatly improved only in part due to the poor thermal conductivity of most polymer systems. Overheating during curing can also be reduced by lowering the concentration of the initiator species in the starting formulation, provided that the reduction in initiator concentration prolongs the curing process and results in incomplete curing reactions and partial Except that it can result in a final body that has only been polymerized exclusively.

[0008] The heat generation and shrinkage associated with polymerization creates a precise part that replicates the contour of the cavity, and to slow the curing reaction and reduce the rapid temperature rise.
It must be accommodated by specially manipulated curing processes (eg, zone curing techniques). The need to use gaskets to prevent leakage (leakage of material) and to minimize the introduction of air bubbles dictates the limited flexibility of machine design. Non-alignment axis offset (de-centration
It is also difficult to arrange the anterior mold half and the posterior mold half in such a way as to deliberately make them known as ion). Further, it is difficult to rotate the two axes to create an intentional tilt (and thus provide prism hardening to the resulting lens).

Finally, most of the time, not all reaction mixtures are initially present in a non-polymerized state, so that low molecular, volatile species do not remain in the finished part. This process must achieve curing of the precursor of all such unreacted materials. This has the effect of delaying the duration of the process, especially if the initiator composition is kept low to minimize the rate of heat generation. In free radical polymerization, this problem is exacerbated by the inhibition of the reaction resulting from the presence of oxygen (dissolved in the polymerization liquid or present in vapor species present around the template). Both nitrogen purging of the polymerization liquid and nitrogen purging of the mold cavity must be used to keep oxygen levels low so that polymerization can take place in a timely manner. Often, nitrogen purging cannot remove all of the oxygen and the part remains only partially cured (especially near the surface of the part), resulting in a sticky or adhesive surface (skin) . Manufacturers have suggested that initiators that react with oxygen diradicals, high levels of initiators (which may be due to high temperature excursions and yellowing (yell)
oxygen-impermeable film on the surface of the cured part is often used to prevent oxygen from slowing down the curing reaction in the adjacent surface area of the cast part. We are implementing. The insertion of such a film limits the opening of the mold after the object has been partially cured, which further has the effect of complicating the process and delaying the process duration.

SUMMARY OF THE INVENTION The present invention discloses an innovative approach that overcomes the above-mentioned essential shortcomings of generally established processes. The present invention is unique in that it promises an extremely economical process suitable for mass production. The present invention also provides parts with accurate dimensions. A second object of this disclosure is a new class of polymerizable materials that exhibit semi-solid behavior during molding, very low inherent shrinkage upon curing, and highly optimized handling properties of the final object It is a prescription.

More particularly, the present invention relates to a method of making a macromolecular network as well as dimensionally stable and accurate,
The present invention relates to a process for the rapid in situ precision mesh-shaped polymerization of semi-solid materials to provide for the production of articles with little or no shrinkage upon curing. The process involves the following steps: mixing the dead polymer, reactive plasticizer and initiator together to provide a semi-solid polymerizable composition; forming the semi-solid composition into a desired shape Exposing the polymerizable composition to a source of polymerizing energy to provide a final product having dimensional stability and high fidelity replication of the inner mold cavity. The articles so produced can optionally be permeable and / or have impact resistance (elasticity). The resulting macromolecular network is characterized by having any of the following i) or ii) or iii): i) semi-interactive reactive plasticizer wrapped around and inside the interlocking dead polymer Penetrating cross-linked polymer network (semi-IPN); ii) interpenetrating cross-linked polymer network of reactive plasticizers in the interlocking dead polymer, the polymer network of the reactive plasticizer further comprising Crosslinked; ii
i) The polymer chains of the interpenetrating reactive plasticizer within the interlocking dead polymer (which can be linear, branched, etc.). In extreme cases, as long as the material can be treated as a semi-solid,
Little or no dead polymer is used, and only reactive oligomers or reactive macromers are used. During polymerization, this arrangement results in an entangled polymer (such as linear or branched) or a single uniform crosslinked polymer network.

When the polymer has a crosslinkable group, the reactive crosslinker can react with the dead polymer chain. In the presence of the polyfunctional monomer, two polymer networks are formed,
It is crosslinked together. Grafting reaction by chain transfer to dead polymer,
It can also occur in addition to network formation of reactive plasticizers between dead polymers. Such a synthesis is desirable because cross-linking of the dead polymer into the network formed by the reactive plasticizer can prevent phase separation between the two polymers. As long as a monofunctional reactive plasticizer is used, linear polymer chains can be formed between dead polymer chains. This arrangement over a crosslinked network for preparing permeable parts is generally not preferred. This is because uncrosslinked polymers have a tendency to phase separate over time (kinetically limited), except in the rare case of compatibility between two or more polymer phases. Mixtures containing only monofunctional reactive plasticizers often react slightly with the dead polymer chains (even when the crosslinkable side groups are not present in the dead polymer), and are preferably Produces a slightly crosslinked network with sufficient stability to prevent phase separation over time.
If the component is an impermeable finished part, the restriction is relaxed.

[0013] The present invention further includes certain semi-solid polymerizable compositions that are useful with the above processes. Semi-solid compositions include a mixture of a dead polymer, a reactive plasticizer, and an initiator. These compositions may optionally include other additives well known in the art to achieve mold release, improved stability or weatherability, non-yellowing properties, and the like.

The present invention allows for a wide choice of reaction chemistry to achieve precise parts with the required mechanical, thermal, optical and other desired properties. This results in a precise part without stress and without cracks, with little or no birefringence. Precise products can be manufactured that are very shock resistant, have a prismatic shape, or have other properties that are desired but previously difficult to achieve.

DETAILED DESCRIPTION OF THE INVENTION The terms “a” and “an” are used herein and in the appended claims.
"Means" one or more. "

The term “dead polymer” as used herein and in the appended claims
Refers to a fully unpolymerized general unreacted polymer. If a particular polymer chemistry is used, the dead polymer can react with the reactive plasticizer, even if the dead polymer does not have unsaturated entities within or attached to the polymer chain. The dead polymer can be a linear or branched homopolymer or copolymer. In the case of a copolymer, the sequence distribution is the sequence or
locky). The block copolymer has a taper (
tapered) or have grafted side chains. The architecture of the dead polymer can be branched, multi-chain, comb-shaped or star-shaped. Diblock, triblock, or multiblock structures are all within the scope of the present invention.

[0017] Semi-solid polymerizable compositions useful for the production of precision parts are, in one embodiment, dead-ended with at least one low molecular species, which is itself polymerizable or crosslinkable. It is prepared by mixing the polymers. This low molecular species
Reference is made herein and in the appended claims to "reactive plasticizers". In another embodiment, the semi-solid polymerizable core composition contains a reactive plasticizer, or a mixture of reactive plasticizers, but no dead polymer. The reactive plasticizer is
It may include monomers, crosslinkers, oligomer reactants, oligomer crosslinkers, or macromer reactants or macromer crosslinks (collectively, macromers). The reactive plasticizer plasticizes the dead polymer, has the desired consistency below ambient temperature (ie, can maintain its shape for easy handling over a short period of time), and has the desired consistency at the processing temperature. (Ie, malleable enough to be compressed or formed into a desired shape). The processing temperature may be conveniently selected to be moderately higher or lower than ambient temperature. The reactive plasticizer can itself be a mixture composed of monofunctional, difunctional, trifunctional, or other multifunctional entities.

Overall, the amount and composition of the reactive plasticizer in the resulting formulation is such that the formulation is semi-solid and can be effectively handled without the need for a gasket in the mold. And the composition. That is, the reactive plasticizer is present in a concentration sufficient to permit malleability and moldability at the desired processing temperatures and pressures; however, the mixture may be at ambient temperature or slightly above ambient temperature. Alternatively, the storage temperature and the mold closure temperature (mold cl) of the material can be conveniently selected to be lower.
Non-drip and do not flow freely for a short period of time in the environment. The amount of reactive plasticizer is
Generally, from about 0.1% to about 100%, preferably from about 1% to about 50%, more preferably from about 3% to about 25% by weight.

The type and relative amount of the reactive plasticizer and the dead polymer dictate the time and temperature dependent viscous-elastic properties of the mixture. The viscous-elastic properties of the selected composition can be wide and variable. For the practice of the invention disclosed herein, the composition only needs to be highly viscous, semi-solid or solid for handling at the same temperature and / or introduction into the mold assembly. Requested,
On the other hand, at processing temperatures where the mold assembly is heated or cooled after closure, it is semi-solid or liquid (ie, deformable). In fact, since all known material systems are more compliant upon heating, the forming temperature is usually, but not necessarily, equal to the handling temperature. In principle, reactive plasticizer systems (with or without dead polymer) that can be treated as semi-solids or solids at the same temperature, as well as reactive plasticizer systems (with temperature (With or without changing and / or using force) can be used in the practice of the invention.

If the mixture comprises most or all of the reactive plasticizer, it may need to be cooled and partially cured to achieve the desired semi-solid consistency for handling. Similarly, the temperature of the mold assembly (the temperature at which the semi-solid composition is introduced into the mold) may be desirably reduced to below ambient temperature to prevent dripping or leakage from the mold before sealing. . However, once the mold is closed, the composition is free to flow at the desired pressure and temperature within the mold cavity to induce the conformation of the material into the internal mold cavity (ie, free at the unhindered molding temperature). This mold can still flow and achieve a composition that can be desirably selected for the molding of densely structured parts in which the molding compound must be filled into small cavities, cannulas, etc. It can be compressed and heated to such pressures and temperatures.

Alternatively, the dead polymer and reactive plasticizer mixture can be selected and mixed in proportions to form a composition that is glassy at ambient temperature and that is rigid. Such a material has all the advantages of facilitating its handling as a semi-solid composition, and allows for a sufficient deformation of the material, so that the material can assume the desired shape and thus be closed It is only necessary that the subsequent mold temperature is adjusted to the softening temperature of the mixture (optionally combined with pressure application).

The most desirable compositions for the practice of the present invention typically comprise from about 3 to about 25% of the reactive plasticizer in the dead polymer. Once combined, this preferred mixture should provide a composition that is semi-solid at room temperature, so that it does not have excessive stickiness or deformability and is easily handled as a separate part or object Can be The mixture can be homogenized more easily at elevated temperatures and can be dispensed as individual parts that approximate the desired shape of the final object, and then cooled for handling or storage. If this preferred mixture or portion is placed in a mold and heated slightly above ambient temperature, or otherwise shaped or compressed while heating, they will have the desired resistance without excessive resistance. Deformed into shape. Such compositions are preferred in that they can be handled and stored at room temperature, while molding or forming into the desired shape can be done at a temperature that is only slightly or moderately away from the surroundings. These and other advantages of the present invention include:
It is described in more detail herein.

When used without or with only a small amount of dead polymer, the reactive plasticizer should be a reactive oligomer or a short reactive polymer (at least 1 With two reactive functional groups). In this case, the reactive plasticizer should be a longer chain length molecule of about 1 to about 1000 repeat units, preferably between about 1 and about 100 repeat units. These reactive plasticizers (or a mixture of reactive plasticizers) are preferably added at a temperature at which the material is handled (eg, inserted into a mold cavity).
It has a high viscosity of more than 000 centipoise and exhibits semi-solid behavior. In the case of low molecular weight reactive plasticizers, this mixture may first be slightly polymerized to produce the semi-solid consistency required for subsequent processing, as disclosed in the present invention. . Alternatively, the mixture can be cooled to create a semi-solid consistency.

[0024] A polymerization initiator is added to the mixture to initiate polymerization after molding.
Such initiators are well-known in the art. If desired, other additives can be added, examples of which include release agents, conventional non-active plasticizers or softeners, pigments that facilitate removal of objects from the mold after curing. Pigments, organic or inorganic fibers or certain reinforcing or bulking fillers, thixotropic agents, indicators, inhibitors or stabilizers (weathering or non-yellowing agents), UV absorbers, interfaces Activators, flow aids, chain transfer agents and the like. This initiator and any other additives, prior to combination with the dead polymer,
It can be dissolved in the reactive plasticizer component, facilitating complete dissolution into the dead polymer and uniform mixing with the dead polymer. Alternatively, the initiator and other optional additives may be added to the mixture just prior to polymerization, which may be preferred if a thermal polymerization initiator is used.

The components in the semi-solid polymerization mixture can be blended by hand or by mechanical agitation.
This component can be slightly warmed, preferably to soften the dead polymer component. Any suitable mixing device can be used to mechanically homogenize the mixture, including, but not limited to, blenders, kneaders, extruders, mills, in-line mixers, fixed mixers, etc. Depending on the ambient temperature, or as needed, above or below atmospheric pressure.

In one presently preferred embodiment of the present invention, any waiting period in which the components are not mechanically agitated may be allowed. This optional waiting period may be provided between the time when the components are first metered in the holding vessel and the time when they are mechanically or manually homogenized. Alternatively, the components can be weighed in a mixing device, and the mixing device is operated for a period of time sufficient to dry blend the components,
An optional waiting period may occur before further mixing takes place. This waiting period can range from one hour to one or more days. This waiting period can be selected empirically and without undue experimentation as the period that provides the most efficient total mixing process in terms of energy consumption. This embodiment of the present invention may be particularly beneficial when the polymerizable mixture includes a high fraction of a dead polymer component, particularly where the dead polymer is glassy or rigid at ambient temperature. The use of a waiting period can also be particularly beneficial if the dead polymer is heat sensitive and cannot be processed at elevated temperatures above its softening point without excessive decomposition for extended periods of time.

“Semi-solid” and “semi-solid” means that the polymerizable composition is essentially a rubbery, toffee-like, bulky material at sub-ambient, ambient, or elevated temperature. . Preferably, the semi-solid bulk material has a sufficiently high viscosity to prevent dripping below ambient temperature and pressure, but is malleable, and the mold cavity is
It can easily deform and conform to the mold surface as a result of the slight heating or the pressure exerted by pressing the two mold halves together, or a combination of both heat and pressure. An advantage of the semi-solid composition is that the semi-solid composition can be preformed, for example, in a slab, disk, or sheet, which is then pressed between mold halves in the absence of a gasket. That is, a lens or other object can be defined. Alternatively, the composition mass may be applied to one side of the mold cavity at a slightly elevated temperature. The other mold half is then contacted with the semi-solid mass, which is squeezed into the final desired shape by the approaching mold half. Again, there is no need to attach a gasket to the mold halves. This is because the composition does not come out of the mold due to its viscous, semi-solid nature (except for extruding the composition in the closing of the mold). In addition, the shaped bulk material can be maintained at a slightly elevated temperature after enclosing by the mold and can anneal, if any, the stress (birefringence) caused by the squeezing, and then form the network ( The system is exposed to a source of polymerization energy (eg, UV light or temperature) to cause curing.

With or without this annealing step, the assembly (ie, the mold front, the rubbery precursor polymerizable composition, and the mold back) is then filled with the reactive plasticizer in the mixture. May be exposed to UV or heat to complete the polymerization of. This reactive plasticizer is semi-interpenetrating (sem) into the entangled dead polymer network.
i-interpenetrating to form a polymer network. In some cases, the reactive plasticizer can react with groups on the dead polymer chains to form a fully crosslinked network. Optimization of the engineering properties can be achieved by appropriate amounts of the constituents of the reactive molecules, their concentrations and compositions.

If dimensional accuracy is required at the edges of the finished part, a precisely adapted (or measured) amount of the reaction mass (bulk material) should be used. The front and rear halves of the mold may be shaped in such a way as to allow a precise nesting within one other. Excess material (if any) during mold closing
Can overflow very small annular areas and can be easily cut off after curing. If the amount of bulk material injected into the mold cavity is measured very accurately,
Such flashes can eventually be eliminated in repeated production of the same finished product.

If the reactive plasticizer, when cured in its pure state, can be designed to exhibit an estimated total shrinkage of around 8%, less than 50% of such plasticizers in the dead polymer The mixture containing the agent gives a very small (less than 4%) total shrinkage (assuming the additive nature of the linearity). The amount of this total shrink is controllable by most cure regimens, including blanket UV exposure (for light cure) and rapid temperature spikes (for heat cure). In certain practical cases, the inherent shrinkage of the oligomer-reactive plasticizer may be about 5%, while the maximum amount used in the formulation for plasticization may be only 10% by weight, The system shrinks only about 0.5%. In certain other practical cases, the inherent shrinkage of low molecular reactive plasticizers can be about 10%, while the maximum amount used in formulations for plasticization is only 5% by weight And only shrinks the system by about 0.5%.

Even when 50-100% of the reactive plasticizer is present, a low degree of shrinkage can be achieved, since the system is not limited to non-viscous flowable components here. In the prior art, the material system is limited by the requirement of low viscosity, which has a high population of reactive entities, and thereby inherently shifts to a system that shows a large degree of shrinkage immediately after curing. Since low viscosity is no longer a requirement of the practice of the present invention, semi-solid material systems with high viscosity, optionally high molecular weight, and inherently low shrinkage may be utilized here.

The molding composition of the invention therefore exhibits a small degree of shrinkage immediately after curing. By "low shrinkage" is meant that the shrinkage of the composition of the invention immediately after curing is typically less than about 5%, preferably less than about 2%. This advantage allows for a molding process in which the fabricated parts exhibit high replication fidelity of the mold cavity. That is, the shrinkage of the polymerizable formulation is very small (typically less than 5%, more preferably less than 2%).
As such, the cured part maintains the shape of the mold cavity through curing. Problems relating to shrinkage, such as premature demolding, which significantly impede and complicate the implementation of the state of the art, are eliminated. Note that the invention can also be practiced with other types of polymerizable systems, such as those initiated with ionic initiators, microwaves, X-rays, electron beams, or gamma radiation. In addition, condensation polymerization, ring opening polymerization, and other polymerization mechanisms may be performed as well.

[0033] The high replication fidelity achieved with the invention disclosed herein can be achieved with optical components that rely on accurate, smooth surfaces (eg, ophthalmic lenses, contact lenses, prisms, optical discs, etc.). ) Can be evaluated in the casting. High fidelity replication also requires components that rely on surfaces with the desired precise topography (eg,
(A printing plate or other pattern transfer medium). High replication fidelity can also be evaluated in the molding of three-dimensional or complex shaped components (couplers, housings, gears, various packaging assemblies, etc.) that require dimensionally accurate replication from the mold. .

The crosslinked interpenetrating polymer network formed during the practice of the invention disclosed herein provides continuous dimensional accuracy during use or handling of the molded part (ie, , Dimensional stability). That is, the crosslinked networks do not flow when heated above their glass transition temperature and provide improved resistance to chemical attack, repeated loading cycles, and the like. The benefits of dimensional stability achieved by the practice of the present invention will be appreciated by manufacturers of all types of moldable objects that may benefit from precise shape.

Another beneficial feature of the invention is that, due to reduced oxygen suppression and slow termination,
Free radical polymerization and other inducible chain polymerization mechanisms (eg, through the use of ionic initiators) are to proceed efficiently in semi-solid media. Without being bound by theory, it is believed that this is due, in part, to the reduced mobility of oxygen molecules in high viscosity media. In addition, oxygen scavenging additives can be incorporated into the polymerizable mixture before the onset of cure. Thus, the semi-solid polymerizable mixture allows for processing with reduced need for nitrogen purging during the mixing and molding steps. The curing reaction also proceeds more completely in the region near the surface of the object to be cured, even when oxygen is present in the gas phase surrounding the object to be cured, and thus the oxygen barrier layer at the surface of the molded part. Reduce or eliminate the need.

[0036] Yet another beneficial feature of the disclosed invention is that thermal spikes caused by polymerization of unsaturated species are mitigated. Conventional casting processes utilize low viscosity systems, which contain close to 100% reactive components. Such systems experience a temperature spike due to the exothermic curing reaction. If the entire part is irradiated and cured at one time, the part temperature can rise sharply, up to 200 ° C. above the part temperature before the start of curing. Excursions at such temperatures lead to thermal decomposition, discoloration, and warpage of the part due to the thermal expansion-shrinkage effect upon removal from the mold.

The semi-solid nature of the inventive polymerizable mixtures disclosed herein significantly reduces such temperature spikes, since the ratio of reactive components in the system is typically The reason is that it is lower than 50% by weight, preferably 25% by weight. Thus, a mixture having only 25% by weight of the reactive plasticizer component will only increase at most approximately 50 ° C. Such elevated temperatures are easily tolerated by most material formulations, and furthermore, such small temperature excursions prevent warping of the demolded parts. Even when the amount of reactive plasticizer is greater than about 50%, the semi-solid composition typically has a low occupancy of reactive entities, thus mitigating high temperature excursions and related problems.

This process enjoys the following advantages: (1) the flexibility of the material formulation, (2) a completed thermoset resin with an interpenetrating network or a slightly cross-linked network. Parts, (3) treatment at room temperature or slightly elevated temperature, (4) UV curing (photopolymerization) not limited by heat transfer time or long cycle time, (5)
) Efficient low-oxygen-in performed in semi-solid media
(6) minimal temperature rise due to exothermic reactions, (7) low pressure operation, and (8) preforms (eg, disks, slabs or packs)
Process or batch operation with intermediate steps of casting from
tch-wise operation).

Two exemplary process schemes are discussed below. Various variants can be envisioned by those skilled in polymerization reaction engineering and polymer processing and molding. Therefore,
The present invention is not limited by these two exemplary processing embodiments.

[0040] Batch processing provides a precision cast from a preform. The dead polymer, reactive plasticizer, and initiator package (optionally containing other additives such as antioxidants, stabilizers) are mixed together in a mixer with temperature control and vacuum capability (Optionally with a waiting period in which the components are not mechanically agitated) to form a semi-solid polymerizable composition without voids and bubbles. The semi-solid composition is discharged from the mixer, and the discharge is cast into slabs (disks, packs, buttons, sheets, etc.), which serve as preforms for subsequent precision casting operations. . Alternatively, the extruded strands of the semi-solid composition can be sliced into preforms or cut into dice. In a subsequent operation, the preform (which may be stored at room temperature or refrigerated for some time or may be further partially cured to facilitate handling and storage) can be recovered and the final article Shaped to the desired shape in production. In a currently preferred embodiment, the preform is sandwiched between the mold halves, and as soon as the mold is closed, if necessary,
Lightly heated to enhance the flexibility of the material and flood exposure by UV (
Flood-exposure) or thermosetting. Anyone can imagine this processing scheme that fits into a just-in-time manufacturing situation, where an inventory of preforms can be used to make accurate parts immediately upon request. In situations where a wide variety of parts must be made just in time, this approach offers exceptional ease of material handling. Eyeglass lenses or contact lenses having a wide range of prescriptions are one example where this batch process scheme is suitable.

In an alternative continuous process, the dead polymer, reactive plasticizer and initiator package (optionally containing other additives such as antioxidants, stabilizers, etc.) are combined together in an extruder. Mixed. If necessary, there is a waiting time before the material is introduced into the extruder, during which time the components are in complete contact with each other but are not mechanically agitated. Periodically, the extruder pours a quantity of a semi-solid reactive plasticizer-dead polymer composition as a warm mass into a temperature-controlled mold cavity. The mold where the front / rear mold assembly is nested is then closed. Any waiting time can occur at an elevated temperature to anneal any stresses caused by the indentation of the mass. Finally, the captured material is flood exposed or thermally cured by UV. This second example process flow is best suited to situations where the number of different parts is small, but each part is a bulk material that is manufactured into many copies. Precision optics constitutes many engineering components with potential applications and complex shapes found in sports equipment, automotive, construction and aerospace industries, and the like.

Material Design Considerations There are at least four basic methods in the literature for developing new polymer systems with unique properties: (1) synthesis of new monomers, (2) new methods of polymerization. And the development of technology, (3) known monomer / crosslinker combinations in such a way that the resulting material has excellent properties, and (4) known polymer blends or alloys. In the present invention, we focus on a fifth new approach, the combination of a dead polymer and a monomer or oligomer reactive diluent. These reactive diluents, when used in small amounts, actually act as plasticizers. Instead of an inert plasticizer that simply remains in the plastic to soften the material, a reactive diluent / plasticizer first softens the polymer and reduces the molding process (conventional unplasticized thermoplastics). Although it can facilitate low temperature molding processes compared to material processing; however, immediately after curing, the polymerized reactive plasticizer fixes the exact shape and morphology of the polymer (and They also fix the plasticizers themselves, so that they cannot leak out or leach out of the material over time).

Once polymerized, the reacted plasticizer no longer softens the dead polymer to the same extent as before curing. The hardness of the cured part is determined by the chemical structure and functional groups of the reactive plasticizers used, their concentration, molecular weight, and the degree of crosslinking and grafting to dead polymer chains. In addition, a chain terminator may be added to the formulation prior to polymerization, to limit the molecular weight and degree of crosslinking of the polymer formed by reacting the plasticizer, and thus the cured part Gives a measure of control in the change in the final mechanical properties of At the same time, the polymerization does not cause significant shrinkage (due to the low total concentration of reactive plasticizer or low occupancy of reactive entities), so that the finished product is dimensionally stable and the high fidelity of the mold cavity Give a copy. Exact shape replication of the mold cavity is further maintained by relatively low molding temperatures and reduced heat generation from polymerization.

Subsequent discussions regarding basic material design considerations fall into two categories based on the type of dead polymer utilizing the process. One category is
Start with a standard thermoplastic as a dead polymer. These include, but are not limited to: polystyrene, polymethyl methacrylate, poly (acrylonitrile-butadiene-styrene), polyvinyl chloride,
Polycarbonate, polysulfone, polyvinylpyrrolidone, polycaprolactone, and polyetherimide. This thermoplastic is optionally added to the polymer backbone with a small amount of a reactive element that is bonded (copolymerized, grafted, or otherwise incorporated) to promote cross-linking upon curing. May be provided. These can be amorphous or crystalline. These may be classified as engineering thermoplastics, or they may be biodegradable. These examples are not meant to limit the scope of workable compositions of the present invention, but merely to illustrate the wide selection of thermoplastics acceptable under the present disclosure. Reactive plasticizer,
It can be mixed with a thermoplastic polymer as listed above to provide a semi-solid composition that can be easily formed into objects of the correct size. Upon curing, the dimensional stability of the object is locked, giving a precise three-dimensional shape or precise surface properties. Thermoplastic polymers have high optical transparency, high refractive index, low birefringence, good impact resistance, good thermal stability, high oxygen permeability, UV transmission or UV blocking, low cost in finished molded objects , Or a combination of these properties.

Another category utilizes “thermoplastic elastomers” as dead polymers. An exemplary thermoplastic elastomer is a triblock copolymer of the general structure "ABA", wherein A is a thermoplastic rigid polymer (i.e., having a glass transition temperature above ambient temperature), and B is an elastomeric (elastic) polymer (glass transition temperature below room temperature). In this pure state, A
BA forms a microphase separated morphology. This configuration consists of a hard vitreous polymer region (A) connected and surrounded by an elastic chain (B). Under certain compositional and processing conditions, this morphology has an associated domain size shorter than the wavelength of visible light. Thus, a portion consisting of such an ABA copolymer can be transparent or at worst translucent. Unvulcanized thermoplastic elastomers have rubber-like properties similar to conventional elastic vulcanizates, but flow as a thermoplastic at temperatures above the glass transition point of the vitreous polymer region. Melting behavior with respect to shear and elongation points is similar to conventional thermoplastics. Important thermoplastic elastomers that are commercially available are exemplified by SBS, SIS, SEBS, where S is polystyrene, and B is polybutadiene, I is polyisoprene, and EB is ethylene. It is a butylene copolymer. Many other diblock or triblock candidates are known, such as poly (aromatic amide) -siloxanes, polyimide-siloxanes, and polyurethanes. SBS and hydrogenated SBS (
That is, SEBS) is a well-known product of Shell Chemicals (Kraton (registered trademark)). DuPont's Lycra® is also a block copolymer.

A thermoplastic elastomer is selected as the starting dead polymer for the formulation,
Exceptionally, the impact-resistant part can be produced by mixing with a reactive plasticizer.
The thermoplastic elastomer itself is not chemically crosslinked and requires a relatively high temperature processing step to form it, which upon cooling is dimensionally unstable,
Produces contracted or distorted parts. If the reactive plasticizer is cured by itself, it can be selected to form a relatively glassy, rigid network,
Or it may be selected to form a relatively soft, elastic network. When the thermoplastic elastomer and the reactive plasticizer are blended together, they form a flexible network having excellent shock absorption and impact properties. "Impact resistance" means the resistance to crushing or crushing when impacted by an accompanying object. Depending on the nature of the dead polymer and reactive plasticizer used in the formulation, the final cured material may be more rigid or more elongated than the starting dead polymer. Composite materials that exhibit excellent robustness can themselves be made by using thermoplastic elastomers that include polymerizable groups along the polymer chain (eg, SBS triblock copolymer).

In addition, if a compatible system is identified, a transparent material can be cast.
"Compatibility" means the thermodynamic state, wherein the dead polymer is solvated by a reactive plasticizer. Thus, sterically similar molecular segments promote mutual dissolution. Generally, the aromatic moiety on the polymer dissolves in the aromatic plasticizer, and vice versa. Hydrophilicity and hydrophobicity are further considered in selecting a reactive plasticizer for mixing with a given dead polymer. If only partial compatibility is observed at room temperature, the mixture often becomes heterogeneous at slightly elevated temperatures; that is, many systems become transparent at slightly elevated temperatures. Such temperatures can be slightly higher than ambient temperature, or can approach up to 100 ° C. In such cases, the reactive components can be rapidly cured at elevated temperatures, locking in the compatible form before cooling the system. Thus, both material and processing approaches can be developed to produce optically transparent parts. Optically transparent and dimensionally accurate parts have a wide range of potential applications. Using both polycarbonate and thermoplastic elastomers, useful formulations can be made by mixing the appropriate reactive plasticizer package.
With the process innovations described therewith, powerful new material systems can be developed.

Preferred formulations for developing optically clear and high impact materials are:
A styrene-rich SBS triblock copolymer containing up to about 75% styrene is used. These SBS copolymers are available from Shell Chemicals (K
raton®), Phillips Chemical Compa
ny (K-Resin®), BASF (Styrolux®), Fina Chemicals (Finaclear®), and Asahi Chemical (Asaflex®). In addition to high impact resistance and good optical clarity, such styrene-rich copolymers preferably have other desirable properties such as high refractive index (ie, refractive index higher than 1.499) and low refractive index. Gives a material system showing the density. These properties are particularly desirable for ophthalmic lenses that enable the manufacture of ultra-thin and lightweight spectacle lenses where thin cross-sectional shapes and wearing comfort are desired.

Alternatively, an elastomer, a thermosetting resin (for example, an epoxy resin, a melamine resin, an epoxy acrylate resin, a urethane acrylate resin (uncured state)),
And other non-thermoplastic polymer compositions may desirably be utilized during the practice of the present invention.

The reactive diluent (plasticizer) can be used alone or using a mixture,
It may facilitate dissolution of a given dead polymer. The reactive functional groups include acrylate,
Methacrylate, acrylic anhydride, acrylamide, vinyl, vinyl ether,
Vinyl ester, vinyl halide, vinyl silane, vinyl siloxane, (meth)
There are silicone acrylate, vinyl heterocycle, diene, allyl and the like. Other, lesser known, polymerizable functional groups can be investigated, such as epoxy resins (including curing agents) and urethane resins (reaction between isocyanates and alcohols). In principle, any monomer can be used as a reactive plasticizer according to the present invention, but with the advantage that it exists as a liquid at room temperature or slightly elevated temperatures, Alternatively, it is easily polymerized by application of a polymerization energy source such as heat.

Reactive monomers, oligomers, and crosslinkers containing acrylate or methacrylate functional groups are well known and are described by Sartomer, Radcure and He.
It is commercially available from nkel. Similarly, vinyl esters are allied Si
Commercially available from Gnal. Radcure also provides UV curable cycloaliphatic epoxy resins. Photoinitiators such as the Irgacure and Darocur series are well known and, like the Sartomer Esacure series,
Commercially available from Ciba Geigy. Thermal initiators such as azobisisobutyronitrile (AIIBM), benzoyl peroxide, dicumyl
l) Peroxide, t-butyl hydroperoxide, and potassium sulphate are also well known and available from chemical suppliers such as Aldrich. Vinyl, diene, and allyl compounds are available as benzophenone from a number of chemical suppliers. Literature on initiators include, for example, Polymer
Handbook, J .; Brandrup, E .; H. See, Immergut, Third Edition, Wiley, New York, 1989. In the following we use acrylates (and in some cases methacrylates) to illustrate the flexibility of the formulation approach. Similar structures with other reactive groups based on small or large molecular structures (eg, acrylamide, vinyl ether, vinyl, diene, etc.) can be used in combination with the disclosed casting process.

[0052] The compatibility of the dead polymer reactive plasticizer mixture is demonstrated by checking the optical clarity of the resulting material at room temperature or slightly above, as exemplified in Example 1 below. I do. To demonstrate the great variety of reactive plasticizers that can be used to achieve such compatibility, only a few are specified from a list of one hundred to one thousand commercially available compounds. For example, monofunctional elements include:
But not limited to: isodecyl acrylate, hexadecyl acrylate,
Stearyl acrylate, isobornyl acrylate, vinyl benzoate, tetrahydrofurfuryl acrylate (or methacrylate), caprolactone acrylate, cyclohexyl acrylate, methyl methacrylate, ethyl acrylate, propyl acrylate and butyl acrylate. Bifunctional elements include, but are not limited to, polyethylene glycol diacrylate, polypropylene glycol diacrylate, hexanediol diacrylate, Photomer 4200 (Henkel), polybutadiene diacrylate (or dimethacrylate), Ebecryl 8402 ( R
adcur), bisphenol A diacrylate, ethoxylated (propoxylated) bisphenol A diacrylate. Trifunctional and multifunctional elements include, but are not limited to: trimethylolpropane triacrylate (and its ethoxylated or propoxylated derivatives), pentaerythritol tetraacrylate (and its ethoxyl) Or propoxylated derivatives), Photomer 6173 (Henkel's proprietary (propr)
ietary), a multifunctional acrylated oligomer), and Sartome
r (SR series), Radcure (Ebecryl series), and He
All groups of nkel (Photomer series) aliphatic and aromatic acrylic acid oligomers.

EXAMPLES The following examples are provided to illustrate the practice of the present invention and are not intended to define or limit the scope of the invention in any manner.

The following Examples 1-8 are designed to develop a thermoset compatible material set prior to polymerization. Examples 9-11 show systems that remain optically transparent upon photocuring, and further illustrate material systems that exhibit high refractive indices. Three-component, four-component and multi-component mixtures can be formulated based on knowledge gained from two-component experiments. Generally, diluents of small molecules have a higher degree of shrinkage. However, they are also typically better plasticizers. In contrast, oligomeric plasticizers shrink less, but they also have lower solvation forces.
lower) and less viscosity reduction. Thus, a mixture of reactive plasticizers is prepared to provide optimized compatibility, processing, and shrinkage properties.

Example 1. Experimental Protocol Dead polymer was added to a vial pre-filled with the intended small amount of reactive plasticizer. The mixture was gently heated while being homogenized by stirring. The resulting semi-solid mass was visually confirmed and recorded as optically transparent at various temperatures. Complete clarity indicates that the ingredients are miscible. The slight haze indicates partial miscibility, and opacity equals incompatibility (
Light scattering as a result of phase separation). Thus, many sets of dead polymer reactive plasticizers can be studied.

Examples 2-8 report some discoveries of system suitability and partial suitability, and then report this procedure.

Example 2. Kraton-based system The following polymers are studied using the protocol described in Example 1. The accompanying table summarizes the properties of the polymer.

[0058]

[Table 1] S = styrene, EB = ethylene butylene, B = butadiene, I = isoprene.

[0059] Hexanediol diacrylate was used for all Krato except G1650.
The n samples were fully solvated, indicating partial miscibility. Ph
The automer 4200 is D1102, D1107, D4141, D4240p
And G1657 are solvated at elevated temperature. Photomer 4200 (oligomer diacrylate) partially solvates G1652. Polybutadiene dimethacrylate (Sartomer CN301) partially solvates D116, D1102, and D4141 at elevated temperatures. Ebecryl8402 is
G1657 is solvated. Isodecyl acrylate can be obtained from all of the above Krato
Compatible with n. Hexadecyl acrylate, lauryl acrylate and stearyl acrylate solvate Kraton at elevated temperatures.

Other monomers that solvate Kraton include butyl acrylate, isooctyl acrylate, isobornyl acrylate, benzyl acrylate, tetrahydrofurfuryl acrylate, and vinyl benzoate. Generally, aliphatic acrylates sufficiently solvate rubbery Kraton. Ethoxylated bisphenol A diacrylate (average molecular weight is 424) has a Kr
Aton D4240p, D1107, D4141, and D1102 are only slightly solvated.

Example 3. Styrene-rich SBS-based Kraton D1401P is a linear styrene-rich SBS triblock copolymer. Reactive plasticizers that solvate Kraton D1401P include vinyl benzoate; tetrahydrofurfuryl acrylate; benzyl acrylate;
Isobornyl acrylate; butyl acrylate; octyl acrylate; isodecyl acrylate; butanediol diacrylate; hexanediol diacrylate; and ethoxylated bisphenol A diacrylate.

To obtain a thermodynamically compatible system comprising a styrene-rich SBS triblock copolymer, Kraton D1401P was purchased from Phillips Chemical
l Company (K-Resin), BASF (Styrolux), Fi
na Chemicals (Finaclear), and Asahi Che
It can be replaced by other SBS copolymers such as those commercially available from Mical (Asaflex).

Example 4 PMMA-Based System This study is performed using a 25,000 molecular weight polymethyl methacrylate (PMMA) sample. Many reactive plasticizers have been found to be compatible with PMMA. This includes Photomer 4200; Photomer
6173; many alkoxylated polyfunctional acrylate esters (eg, propoxylated glycerol triacrylate); urethane acrylates (eg,
Ebecryl 8402 (aliphatic) and Ebecryl 4827, 4849 and 6700 (aromatic)); tetrahydrofurfuryl acrylate; benzyl acrylate; butyl acrylate; butanediol diacrylate; hexanediol diacrylate; octyldecyl acrylate; isobornyl acrylate; and ethoxylation There is bisphenol A diacrylate.

Example 5 Polystyrene-Based System Acrylic plasticizers that solvate polystyrene include Photomer 4200
, Tetrahydrofurfuryl acrylate and isodecyl acrylate. Bisphenol A diacrylate, hexadecyl acrylate, and stearyl acrylate are compatible at elevated temperatures (eg, about 100 ° C.).

Example 6 Polycarbonate-Based Systems Bisphenol A diacrylate, alkoxylated bisphenol A diacrylate, cycloaliphatic epoxy resins, N-vinyl-2-pyrrolidinone, and tetrahydrofurfuryl acrylate are particularly elevated. It has been found to be useful for solvation of polycarbonate at temperatures. Some aromatic urethane acrylates can be mixed with the compounds described above to aid in the compatibility of this component.

Example 7 ARTON-Based System Reactive plasticizers that solvate ARTON FX4727T1 (JSR Corporation) include benzyl acrylate; isobornyl acrylate; isobornyl methacrylate, butyl acrylate; octyl acrylate. Isooctyl acrylate; isodecyl acrylate; lauryl acrylate; behenyl acrylate. Aliphatic acrylates very well solvate ARTON.

Example 8. ZEONEX based system Octyldecyl acrylate, butyl acrylate,
And isooctyl acrylate are available from Zeonex 480R (Nippon
Zeon Co. , Ltd) are solvated. Isobornyl acrylate is Ze
onex 480R and E48R, and Zeonor 1420R, 10
Solvate 20R and 1600R. Lauryl acrylate and behenyl acrylate solvate ZEONEX 480R and E48R at elevated temperatures.

Example 9. Transparent photocuring system A mixture comprising a dead polymer, a reactive plasticizer, and a photoinitiator was mixed according to the protocol described in Example 1. The amount of reactive plasticizer is typically between 3% and 25%
And the photoinitiator was 1% to 5% by weight. The photoinitiators of the examples were Sartomer's Esacure KT046 and Ciba Geigy.
Irgacure 184.

The resulting semi-solid composition was slightly heated (up to about 100 ° C.), pressed between flat glass plates, and flood exposed by UV light (flood-e).
xpose). Rapid polymerization has been observed to lead to transparent and semi-solid materials.

Examples of transparent light-curing systems include: Kr reported by Example 3
system based on aton D1401P; PMMA reported by Example 4
Based system; ARTON based system reported by Example 7. K
Systems based on raton D1401P also showed excellent impact resistance.

Example 10 Transparent Photocuring System with High Refractive Index A mixture comprising a dead polymer, a reactive plasticizer, and a photoinitiator is mixed according to the protocol described in Example 1 and performed. Further processing was as described in Example 9. The dead polymer was Kraton D1401P and the reactive plasticizer was benzyl acrylate, which was mixed in a 88/12 weight ratio. Irgacure 184 was added to 2% by weight of the mixture, based on the total weight of the system. After UV curing, a flat sample having a thickness of 2.4 mm was produced, which showed a light transmission of 88% at a wavelength of 700 nm. The refractive index of the cured sample was 1.578 at room temperature sodium D line.

Example 11 Permeation System Utilizing Standby Time Kraton D1401P and isooctyl acrylate were added to a glass container in a weight ratio of 93/7. The capped container was allowed to stand overnight. After 24 hours, the mixture was a clear, semi-solid mass. Irgacure 184 was added to the mixture to 2% by weight (based on the total weight of the system), slightly heated and dissolved in the system with manual mixing. The resulting semi-solid mass was further processed as described in Example 9. After UV curing, a flat sample having a thickness of 2.3 mm was produced, which showed 90% light transmission at a wavelength of 700 nm. The refractive index of the cured sample was 1.574 at room temperature sodium D line.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08J 5/00 CFD C08J 5/00 CFD G02B 1/04 G02B 1/04 // B29K 21:00 B29K 21: 00 69:00 69:00 B29L 11:00 B29L 11:00 (81) Designated country EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, IT, LU , MC, NL, PT, SE), OA (BF, BJ, CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, K) E, LS, MW, SD, SL, SZ, TZ, UG, ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AE, AL, AM, A , AU, AZ, BA, BB, BG, BR, BY, CA, CH, CN, CU, CZ, DE, DK, EE, ES, FI, GB, GD, GE, GH, GM, HR, HU, ID, IL, IN, IS, JP, KE, KG, KP, KR, KZ, LC, LK, LR, LS, LT, LU, LV, MD, MG, MK, MN, MW, MX, NO, NZ , PL, PT, RO, RU, SD, SE, SG, SI, SK, SL, TJ, TM, TR, TT, UA, UG, US, UZ, VN, YU, ZA, ZW Houston, Michael United States California 94709, Berkeley, Martin Luther King Jr. Way No. 1429 (72) Inventor Toshiaki Hino California 94709, United States Berkeley, Spruce Street 1786, United States Statement 109 F-term (reference) 4F071 AA02 AA12X AA22X AA33 AA50 AA78 AF07 AF23 AF54 AH07 AH19 BA08 BA09 BB01 BB12 BC17 4F204 AA04E AA12E AA13E AA21E AA28 AA44 AA45 AB03 PA04 AB07 AH01 EB01 PA07 GBH QA03 QA12 QA13 QB05 UA01 VA04 WA07 4J026 AA07 AA17 AA25 AA45 AA61 AA62 AA68 AA69 AB34 AC11 AC12 AC15 BA26 BA28 BA29 BA30 BA46 BA50 DB05 DB07 DB24 DB33 DB36 FA09 GA06 GA08

Claims (44)

[Claims] 1. A polymerizable composition comprising a mixture of a dead polymer, a reactive plasticizer and an initiator, wherein the polymerizable composition is semi-solid, adaptable, and polymerized. A composition that exhibits a low degree of shrinkage. 2. The polymerizable composition of claim 1, wherein the reactive plasticizer is less than 50% by weight of the composition. 3. The polymerizable composition of claim 1, wherein the reactive plasticizer is less than 25% by weight of the composition. 4. A polymerizable composition comprising a mixture of a reactive plasticizer and an initiator, wherein the polymerizable composition is semi-solid, adaptable, and A composition exhibiting a low degree of shrinkage. 5. The polymerizable composition according to claim 1, which is transparent at ambient or elevated temperatures. 6. The polymerizable composition according to claim 1, wherein said dead polymer is a thermoplastic elastomer. 7. The polymerizable composition according to claim 1, wherein the reactive plasticizer forms an impact network when polymerized. 8. The polymerizable composition according to claim 1, wherein the reactive plasticizer forms a network structure exhibiting high fidelity replication upon polymerization. 9. A polymer network, wherein the network comprises: a semi-solid polymer, mixed together with: a dead polymer, a reactive plasticizer, an initiator, and optionally other additives. Forming a possible composition; shaping the semi-solid composition into a desired shape; and exposing the composition to a source of polymerization energy to obtain the polymer network. Mesh structure. 10. A polymer network, wherein the network comprises: a semi-solid polymer, mixed together with a dead polymer, a reactive plasticizer, an initiator, and optionally other additives. Forming a possible composition; forming the semi-solid composition into a preform; placing the preform in a mold; compressing and / or heating the mold, resulting in the semi-solid The composition is
Shaping the interior cavity of the mold; and exposing the composition to a source of polymerization energy to obtain the polymer network. 11. A semi-solid polymerizable composition comprising a polymer network, comprising: a reactive plasticizer, an initiator, and optionally other additives, mixed together. Forming the article; shaping the semi-solid composition into a desired shape; and exposing the composition to a source of polymerization energy to obtain the polymer network. 12. A polymer network, comprising: a semi-solid polymerizable composition comprising: a reactive plasticizer, an initiator, and optionally other additives mixed together. Forming the article; forming the semi-solid composition into a preform; placing the preform in a mold; compressing and / or heating the mold so that the semi-solid composition is ,
Shaping the interior cavity of the mold; and exposing the composition to a source of polymerization energy to obtain the polymer network. 13. The polymer network according to claim 9, wherein after the step of shaping the composition and before the step of exposing to the polymerization energy source, at a predetermined temperature. The polymeric network further comprising providing a waiting period. 14. The polymeric network of claim 9, 10 or 13, wherein the reactive plasticizer comprises less than about 50% by weight of the composition. 15. The polymeric network of claim 9, 10 or 13, wherein the reactive plasticizer comprises less than about 25% by weight of the composition. 16. The polymer network according to claim 9, wherein the polymer network is transparent. 17. The polymer network according to claim 9, wherein said polymer network has a high refractive index.
6. The polymer network structure according to any one of 5. 18. The polymer network according to claim 9, wherein the reactive plasticizer forms an impact network when polymerized. 19. The polymer network according to claim 9, wherein the dead polymer is a thermoplastic elastomer. 20. The polymer network according to claim 9, wherein the dead polymer is a high-performance engineering thermoplastic resin. 21. The method of claim 9, wherein said dead polymer is polycarbonate.
19. The polymer network structure according to any one of claims 10 and 13 to 18. 22. The polymer network structure according to claim 9, which exhibits a low degree of shrinkage upon curing. 23. A polymeric network according to any one of claims 9 to 21 that exhibits high fidelity replication. 24. A method of forming an article, comprising: mixing together a dead polymer, a reactive plasticizer, an initiator, and optionally other additives, to form a semi-solid. Forming the semi-solid composition into a desired shape; exposing the composition to a source of polymerization energy; and obtaining the resulting article. 25. A method of forming an article, comprising the steps of: mixing a dead polymer, a reactive plasticizer, an initiator, and optionally other additives together to form a semi-solid. Forming the semi-solid composition into a preform; providing a mold body of at least two parts, the parts defining an internal cavity between the parts. Defining, wherein the cavity corresponds to a desired shape; placing the preform in the interior cavity of the mold; compressing and / or heating the mold so that the semi-solid composition comprises:
Shaping the interior cavity of the mold; exposing the composition to a source of polymerization energy; and obtaining the resulting article. 26. A method of forming an article, comprising the steps of: mixing together a reactive plasticizer, an initiator, and optionally other additives to form a semi-solid polymerizable material. Forming a semi-solid composition into a desired shape; and exposing the composition to a source of polymerization energy. 27. A method of forming an article, comprising: mixing together a reactive plasticizer, an initiator, and optionally other additives to form a semi-solid polymerizable material. Forming the semi-solid composition into a preform; providing a mold body of at least two parts, the parts defining an internal cavity between the parts; Placing the preform in the interior cavity of the mold; compressing and / or heating the mold so that the semi-solid composition comprises:
Shaping the interior cavity of the mold; exposing the composition to a source of polymerization energy; and obtaining the resulting article. 28. The method according to any of claims 22 to 27, wherein the method comprises the steps of: forming a composition after forming the composition and exposing the composition to a source of polymerization energy. The method further comprising providing a waiting period at the temperature. 29. The method according to any of claims 22 to 27, wherein the mixing step comprises a waiting period in which the components are not mechanically agitated. 30. The method of claim 24, 25, 28 or 29, wherein said reactive plasticizer comprises less than about 50% by weight of said composition. 31. The method of claim 24, 25, 28 or 29, wherein said reactive plasticizer comprises less than about 25% by weight of said composition. 32. A shaped article comprising a semi-interpenetrating polymer network of a reactive plasticizer within an entangled dead polymer. 33. A shaped article, wherein the article comprises an interpenetrating crosslinked polymer network of a reactive plasticizer within an entangled debt polymer, wherein the reactive plasticizer polymer network comprises the dead polymer. The article is further crosslinked. 34. A shaped article comprising interpenetrating reactive plasticizer polymer chains within an entangled dead polymer. 35. The shaped article of claim 32, 33 or 34, wherein the reactive plasticizer comprises less than about 50% by weight of the composition of the article. 36. The shaped article of claim 32, 33 or 34, wherein the reactive plasticizer comprises less than about 25% by weight of the composition of the article. 37. The shaped article of any of claims 32-36, wherein the article is transparent. 38. The shaped article of any of claims 32-36, wherein the article has a high refractive index. 39. The shaped article of any of claims 32-38, wherein the dead polymer is a thermoplastic elastomer. 40. The shaped article of any of claims 32-38, wherein the dead polymer is a high performance engineering thermoplastic. 41. The dead polymer is a polycarbonate.
An article shaped according to any of claims 2 to 38. 42. The article as cast, wherein the article is impact resistant.
An article shaped according to any of the preceding claims. 43. The shaped article of any of claims 32-42, which exhibits a low degree of shrinkage upon curing. 44. The shaped article of any of claims 32-42, which exhibits high fidelity reproduction.